Plate type undulating flue boiler



Sept. 15, 1953 J. A. GRACE PLATE TYPE, UNDULATING FLUE BOILER Filed Jan. 16, 1951 INVENTOR AGENTS 3a `lAmxis A. GRACE BY 67m@ 7' Patented Sept. 15, 1953 UNITED STATES PATENT OFFICE 2 Claims.

This invention relates to steam generating apparatus and more particularly to a heat exchange apparatus for use as a boiler or a heating unit.

It is an object of this invention to produce a novel steam generating apparatus.

It is a further object of this invention to provide a boiler which will occupy a minimum of space.

It is also an object of the present invention to provide a boiler that may be fabricated from standard stock materials and which is of a very rugged construction.

It is a further object of this invention to provide a heat exchange means that will enable the maximum heat energy to pass from the gas to the water in a steam generating apparatus thus bringing about greater eiciency.

Another object of the present invention is the provision of a novel boiler unit that can be adapted to use in present furnace installations.

Although the novel features which are believed to be characteristic of this invention will be particularly pointed out in the claims appended hereto, the invention itself, as to its objects and advantages, the mode of its operation and the manner of its organization may be better understood by referring to the following description taken in conjunction with the accompanying drawings in which:

Figure 1 is a perspective view of the heat exchange unit of the present invention.

Figure 2 is a side elevational section view of a furnace embodying the instant invention taken along the line 2-2 of Figure l and looking in the direction of the arrows.

Like reference characters denote like parts in the several figures of the drawings.

ln the past, it has been the practice to bring about heat exchange between the heating substance and the material to be heated by means of thin, cylindrical tubes. For instance, in some steam generating apparatus the hot gases arising from the furnace are carried through tubes of circular cross-section and these tubes pass through a chamber carrying the water; this is the fire-tube boiler. Also, the water may be carried in the tubes, constituting the so-called water-tube boiler. The tube construction has many disadvantages. Chief among these disadvantages is the fabrication, requiring, as it does, a great deal of skilled hand labor. Furthermore, the tube construction is very bulky and expensive and does not lend itself very Well to the compact, inexpensive heating units needed in average-type homes. Previous attempts to use other than tube construction in small units, such as are used in the home, have resulted in very inefficient steam generation. The present invention obviates these diiculties by the use of a welded unit made from plate material, as will be described below.

Referring first to Figure 1, which best shows the structure of the heat exchange unit, the boiler unit is generally designated I0. The boiler unit is made up from steel plate and is of a generally elongated box-like configuration. It is made up of a rectangular top wall II', a front wall I2, a back wall I3, and two side walls I4. A door opening I5 is provided in the lower portion of the front wall I2 and a iiange I5 is provided around the opening. The corner representing the junction of the top wall II and the front wall I2 is formed with a plurality of rectangular water recesses I 1. These water recesses are formed by slotting the forward edge of the top wall and the upper edge of the front wall and then welding side plates I8, back plates I9, and bottom plates 2D together and to the edges of the slots to form the water recesses. In the preferred embodiment, there are five of these water recesses and the space between them is the same as their width. Also, the recesses extend from the top of the front wall a distance about two-thirds of its height; the recesses extend backwardly from the front edge of the top wall a distance about equal to one-half of the distance from the front to the back of the top wall.

The side walls I4 of the boiler unit I@ are apertured in the portion not adjacent to the recesses I 'I' and the edges of corresponding apertures in the two side Walls are joined by plates to form water passages running transversely through the body of the boiler unit, these water passages being about as wide as the recesses Il. Two of these apertures, namely 2l and 22, extend from closely adjacent to the bottom edges of the side walls to points about two-thirds of the distance up the sides. The water passages 2l is adjacent to but spaced from the back wall I3. The water passages 22 is adjacent to but spaced from the back plates I9 of the recesses Il. Both water passages 2l and 22 are formed with pointed roof portions 23. A water passage 24 passes from side wall to side wall of the boiler at a point considerably closer to the water passage 22 than to the water passage 2|. The water passage 24 extends downwardly from the top wall to a point about a third of the distance from the bottom to top of the unit. There are two water passages and 26 between the water passage 2| and the water passage 24 and there is a water passage 21 between the water passage 24 and the water passage 23. The three water passages 25, 26, and 21 are similar; their roof portions are pointed and are on a level with the roof portions 23 of water passages 2| and 22; their bottom portions are on a level with the bottom portion of the water passage 24. All of these water passages are of a width about the same as the recesses I1 and are spaced apart at distances equal to their widths. The unit is further provided with a stack tube 28. In general, then, the unit I8 comprises an elongated box-like member with thin, broad, vertical water recesses running longitudinally in the forward portion and thin, broad, vertical with passages running transversely in the rearward portion.

The boiler unit i!) shown in Figure l is used in a furnace in the manner shown in Figure 2. The furnace, generally designated 23, comprises a box-like enclosure 39 made of steel plate and having a top wall 3|, a front wall 32, a rear wall 33, side walls 34, and bottom wall 38. The front wall of the furnace enclosure is provided with an aperture to receive the ange I6 of the unit I0; the flange i5 is provided with a door closure 36. The rear wall 33 of the furnace enclosure is provided with an aperture 31 through which passes the stack tube 28. When the unit I8 is situated within the furnace enclosure and the bottom edges of the sides, front, and rear walls of the unit ID are joined to the side, rear, and front walls of the furnace enclosure, respectively, by plates 39 welded therebetween, a fluidn tight water chamber 48 will be formed in the upper part of the furnace. This upper chamber 48 will be defined by the top, front, rear, and side walls of the boiler unit, the top, front rear,

and side walls of the furnace enclosure, the water passages, the water recesses, and, lastly, the joining plates 39.

The furnace is further provided with a separator plate 46 extending transversely of the furnace enclosure from side wall to side wall thereof. This separator wall extends vertically from the bottom of the water passage 22 to the bottom 38 of the furnace enclosure. A horizontal platform 4I extends from the separator plate 40 to the back wall 33 of the furnace enclosure and this platform supports a fly-ash tray 42 which extends from side wall to side wall and from separator plate to back wall of the furnace enclosure. The tray 42 is provided with a vertical partition 43. In other words, the two partitions 43 and 44 are aligned with the water passage 2| and with each other and form a solid wall from the bottom of the water passage to the bottom of the tray. A door 45 is provided in the rear wall of the furnace for access to the tray. The space defined by the side walls of the furnace enclosure, the separator plate, and the front wall is the combustion chamber 49 and is provided with a retort 46 for holding the fuel. In the drawing,

coal 41 is shown being burned, but, of course, a,-

apparatus or hot-water heating means, this, of f course, would be the water. As shown in Figure 2, the water fills the area between the top wall of the boiler and the top wall of the furnace enclosure; the water also resides between the side walls of the furnace enclosure and the side,

Walls of the boiler, the front wall of the furnace enclosure and the front wall of the boiler, and the back Wall of the furnace enclosure and the back wall of the boiler. More important, however, is the fact that the water is free to reside in the water recesses I1 and the water passages 2 I, 22, 24, 25, 26, and 21 all of which open into the chamber 48, directly or indirectly. The stack tube 28 is connected to the flue or chimney. The fuel is introduced and combustion takes place in the chamber 49. As shown in the drawing by means of arrows, the hot gases of combustion pass upwardly between the water recesses I1. The gases are deflected by the top wall I I of the boiler yand the side wall of the water passage 22 into the space over the water passages 22 and 21. The gases are then deflected by the top wall of the boiler and the side wall of the water passage 24 and are forced to pass downwardly in the space between the water passages 24, 21, and 22. The gases thus arrive under the water passages 25, 26, 24, and 21 and flow from there upwardly through the space between the water passages 2|, 25, 26, and 24. The gases arrive in the space over the water passages 2|, 25, and 26 and ow from there downwardly between the water passage 2| and the back wall I3 of the boiler and thence outwardly through the flue tube. It can be seen then that heat transfer takes place between the hot gases and the water in a very desirable manner. Heat reaches the water not only through the walls of the water passages and the water recesses, but also through the top, front, back and side walls 0f the boiler unit. All the surfaces that have any horizontal component in the path of the gases are inclined so that fly-ash will slide off instead of accumulating and acting as an insulation, thus cutting down the eiiiciency of the unit. The fly-ash is precipitated from the gas by contact with the walls of the water passages and falls into the tray 42 from which it may be removed; the removal of the fly-ash from the eiiiuent gases is desirable for many obvious reasons. The separator plate 4G and the partitions 43 and 44 aid in determining the flow path taken by the gases.

While certain novel features of the invention have been shown and described and are pointed out in the annexed claims, it will be understood that various omissions, substitutions, and ch-anges in the forms and details of the device illustrated and in its operation may be made by those skilled in the art without departing from the spirit of the invention.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

l. A boiler unit for use in a domestic heating apparatus comprising an open-bottomed, box-like enclosure having a 'top wall adapted to be situated horizontally and further having a front, a back, and two side walls adapted to be situated vertically, said top and side walls being of generally elongated rectangular shape with the long dimensions adapted to extend horizontally, the edges of the top and front walls where these walls intersect being slotted, the sides of the slots in the top wall extending parallel to the side edges for about half the length of the unit and being equally spaced and equally wide, the slots in the front wail matching those of the wall and extending parallel to the vertical sides of the unit for most of its height, recess walls extending inwardly from the edges of the slots perpendicularly to the planes of the tcp and front walls, said recess walls forming thin, broad water recesses which extend longitudinally of the unit from the front wall, the side walls in the rearward portion of the unit being provided with a plurality of generally vertical, elongated rectangular slots which are spaced from one another, each slot in one side wall having a complementary slot in the other side wall, the edges of said complementary side wall slots being joined by walls which are perpendicular to the side walls and which form a series of thin, broad water passages extending transversely of the unit, the said water passages being equally spaced longitudinally of the back portion of the unit and being equally wide, the foremost and the rearwardrnost of said water passages extending upwardly from the bottom edges of the side walls of the unit to positions spaced from the top wall, at least one intermediate water passage extending downwardly from the top wall to a position spaced from the bottom edges of the side walls, the water passages between the forwardmost, the rearwardmost, and the intermediate Water passages extending upwardly only as high as the said forwardmost and rearwardmost Water pas- 6 sages and extending downwardly only as far as the said intermediate water passage.

2. A boiler unit as recited in claim 1 wherein all surfaces of said water passages which have any upwardly-forcing horizontal component are substantially inclined to the vertical.

JAMES A. GRACE.

References Cited in the le of this patent UNITED STATES PATENTS Number Name Date '7,935 Champion Feb. 18, 1851 123,153 Clay Jan. 30, 1372 381,368 Hayna Apr. 17, 1888 693,870 Kuen et al. Feb. 25, 1902 1,031,239 Brenner et al. July 2, 1912 2,128,842 Morgan Aug. 30, 1938 2,142,626 Anderson et al. Jan. 3, 1939 2,228,602 Kolb Jan. 14, 1941 2,553,549 Carter May 22, 1951 FOREIGN PATENTS Number Country Date 3,473 Great Britain Mar. 4, 189() 786,183 France Aug. 28, 1935 

